The present invention relates to a method for advancing and supporting an underground mine gallery in which the contour of the cross-section of the mine gallery is produced by a mining machine and in which the cross-section of the mine gallery is held open and supported by a plurality of support frames arranged spaced from each other in the longitudinal direction of the mine gallery in which the support frames may eventually yield to a limited degree under the pressure of the surrounding rock.
On the other hand, the invention also relates to a machine, as well as to support frames for carrying out the method.
Machines for advancing an underground mine gallery are known, which are used to cut minerals from the whole mine face to thereby obtain the desired contour of the mine gallery. The tools of such machines cut thereby substantially the complete mine face. Such machines and the operation thereof are not only very expensive, so that their use is only warranted during advancing of mine galleries for a considerable length, but in addition thereto, due to the construction of such mining machines, it is possible to place support frames only at a distance from the portion of the mine gallery which is opened at any instant by the mining machine. Depending on the structure of the surrounding rock, such a delay of proper support may lead to dangerous situations. Furthermore, the cross-section of an underground mine gallery produced by a full-cut mining machine is usually limited to a circular form. In addition, considerable difficulties are encountered to insert and properly set the usually trough shaped, and under the pressure of the surrounding rock slightly yieldable, supports parallel to the continuous advance of such a full-cut mining machine.
Advancing mining machines are also known which cut only successive parts from the mine face, by means of which, however, it is not possible to produce an exact contour of the desired cross-section of the mine gallery. Due to the kinematics of such machines, sawtooth shaped profiles and irregular breaks are produced in the thus formed walls of the mine gallery, which requires a backfilling in order to assure a proper abutment of the support means against the surrounding rock. It is further of disadvantage that delay of proper support of the freshly formed portion of the underground mine gallery cannot be avoided since such supports can be put in place only after all of the loose material formed during the cutting operation is transported away from the mine face. The stability of the surrounding rock is therefore necessarily impaired.
The above mentioned disadvantages are also present when the mine gallery is advanced by a boring-and-blasting operation.
In connection with the known methods for advancing a mine gallery and the thereby used means, considerable difficulties are also encountered to properly correlate the advancing or mining operation, on the one hand, with the supporting operation, on the other hand, so that as many as possible operations can be carried out simultaneously, in order to maintain the speed at which the underground mine gallery is advanced within an economically affordable range.